Explain why an employee who cares only about expected return and volatility will likely underweight the amount of money he invests in his own company’s stock relative to an investor who does not work for his company.

For Problems 27–29, refer to the following table of estimated factor betas based on data from 2007–2017.
Factor MSFT XOM GE MKT 1.10 0.66 1.22 SMB -0.71 -0.38 -0.29 HML -0.01 0.17 0.78 PR1YR 0.02 0.21 -0.17